Adult mice cloned from migrating primordial germ cells.
Adult mice cloned from migrating primordial germ cells.
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DOI：
10.1073/pnas.0504943102
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发表时间：
2005-08
影响因子：
11.1
通讯作者：
Y. Yamazaki;Eleanor W. Low;Y. Marikawa;K. Iwahashi;M. Bartolomei;J. McCarrey;R. Yanagimachi
中科院分区：
文献类型：
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作者：
Y. Yamazaki;Eleanor W. Low;Y. Marikawa;K. Iwahashi;M. Bartolomei;J. McCarrey;R. Yanagimachi
我们先前报道，性腺生殖细胞在性交后11.5-19.5天(DPC)的基因组不能支持克隆小鼠胚胎的完全发育。在这项研究中，我们使用早期阶段的原始生殖细胞(PGC)在8.5-10.5DPC进行了核移植。将8.5、9.5和10.5DPC的PGC核移植到去核的卵母细胞中，有7个克隆胚胎发育成足月后代。在这些细胞中，有5个都来自8.5或9.5-DPC PPC，发育成具有正常生育能力的健康成年人。在剩下的两个来自10.5-DPC的后代中，一个在出生后不久死亡，另一个表现出轻微的生长迟缓，但随后发育成可育的成虫。我们检测了9.5-至11.5-DPC中印记的H19和Snrpn基因座上的等位基因特异性甲基化。虽然在9.5dpc时，H19等位基因的甲基化开始明显消除，但大多数PGCs直到10.5dpc才表现出显著的父本等位基因特异性甲基化的消除。母体等位基因特异性甲基化在10.5dpc时从Snrpn中基本消除。到11.5DPC时，大多数PGC显示H19和Snrpn中的等位基因特异性甲基化几乎完全或完全消除。这些结果表明，至少有一些基因组印记在8.5-9.5-DPC的PGC中基本保持不变，然后在PGC进入生殖器脊时，在大约10.5DPC的情况下经历擦除。因此，8.5-9.5DPC的移行PGCs可以成功地用作核移植的供体，而11.5DPC及以后的性腺PGCs不能支持完全发育。
We previously reported that the genomes of gonadal germ cells at 11.5-19.5 days postcoitum (dpc) are incompetent to support full-term development of cloned mouse embryos. In this study, we performed nuclear transfer using primordial germ cells (PGCs) from earlier stages at 8.5-10.5 dpc. When PGC nuclei at 8.5, 9.5, and 10.5 dpc were transferred into enucleated oocytes, seven cloned embryos developed into full-term offspring. Of these, five, all derived from 8.5- or 9.5-dpc PGCs, developed into healthy adults with normal fertility. Of the remaining two offspring derived from 10.5-dpc PGCs, one died shortly after birth, and the other showed slight growth retardation but subsequently developed into a fertile adult. We examined allele-specific methylation at the imprinted H19 and Snrpn loci in 9.5- to 11.5-dpc PGCs. Although the beginning of methylation erasure was evident on the H19 paternal allele at 9.5 dpc, most PGCs did not demonstrate significant erasure of paternal allele-specific methylation until 10.5 dpc. Maternal allele-specific methylation was largely erased from Snrpn by 10.5 dpc. By 11.5 dpc, the majority of PGCs showed nearly complete or complete erasure of allele-specific methylation in both H19 and Snrpn. These results demonstrate that at least some genomic imprints remain largely intact in 8.5- to 9.5-dpc PGCs and then undergo erasure at approximately 10.5 dpc as the PGCs enter the genital ridges. Thus, migrating PGCs at 8.5-9.5 dpc can be successfully used as donors for nuclear transfer, whereas gonadal PGCs at 11.5 dpc and later are incompetent to support full-term development.